If you remove one from eleven, it becomes ten. If you remove one from nine, it becomes ten.

How is this possible?

A chess tournament is taking place on knock-out terms (the one who loses the match is out of the game).
(a) If 10 matches are played in total, how many players participated?
(b) If 20 players took part in the tournament, how many matches were played?

I’m light as a feather, yet the strongest person can’t hold me for five minutes. What am I?

The host of a game show offers the guest a choice of three doors. Behind one is an expensive car, but behind the other two are goats.
After you have chosen one door, he reveals one of the other two doors behind which is a goat (he wouldn't reveal a car).

Now he gives you the chance to switch to the other unrevealed door or stay at your initial choice. You will then get what is behind that door.

You cannot hear the goats from behind the doors, or in any way know which door has the prize.

Should you stay, or switch, or doesn't it matter?

When we see 2 but call 10?

Find the next number in the series

12, 20, 40, 72, 116, 172 ?

There were five men at church, and it started raining while they were outside. The four that ran still got wet, but the one that was still stayed completely dry. Why did he stay dry?

What is the largest number you can write with just 3 digits?

Find out the number of circles in the given picture having Illusion

Which is Odd One Out and why?

4377

3954

9862

8454

9831